Electrical transformer



March 2 1926. "1575,342

A. A. HOWARD ELECTRICAL TRANSFORMER Filed July 9, 1925 I Qjparts broken.avvay Fig." 2 is a' view. taken "as-indicated byithe line-2 of Fig. 1,and

Patented-' lMar. i I

To iitiartay I Be it known that I, Aos rN .i W IdoivARD', 'citizlen 'ofthe United? States, residing at Ghica o ,{in theycounty of (lookand-State of Illinois, have invented a new-and useful Improvement in"Electrical ;l-ransformers,

' of which the following is a specification.

hi inv'ention relates to improvements in hereshown the inventiOiasiembodied in a of Waves at radiofrequenc transformermsuch as is usedin connection, with radio; apparatus forthe ampllfication i v o r air.The outer or SGCOIldtLI'Y'COll of Wire 14 are employed, a primary-coiland a second- '-.uy; coil. 7' These-coils are-arranged in induc tiverelat on'to each other and .must be supported properly in this position.the

use of my invention I am able to do 'thismod fications.

' in a very simple manner.

ventioni ivill appear more fully. as I proceed panying drawings, Figure1;;is a top :plan view of I complete transformer showing i ,Fig. 3Iisa'view on an enlarged-scale taken as indicated by the line'3of Fig. 1.

As shown in the draWings,:1O indicates a cylindricalv supportingmemberhere shown as made of insulating material such as fibre,

'bakelite, hard rubber or th-elike.

In the outer surfaceofthe member is cut a'spiral groove'll. :The'turnsofthis groove ll are spaced apartthe distance at which. it,is* desiredto space the turns of i the primary coil. The groovell 'is made withadepth equal to the distance which it is desired to space .theprlmaryorinner c011 fromthe secondary or'outer coil. Obviously,

the Wallof the member '10 must be of sufiicient thickness to permit therequisite depth of the groove 11 andstill' furnish sufficient.

strength to'support the Wires.

bottom of the'groove 'llgandis here shown asfloeing .either bare jvvireor insulated by enamel. Preferably theisupport'ing member In 'making@such;transformers, two, coils ELECTBI QZ L L 'rnausromvinnf. 7

atpiicationiiieaJ 11 ;9,=1925., seriar No'. 42,41 1. I

each other bythe groove 11. I Wound on the outer surface'of thesupporting member 10 and covering the groove I 11 is a sheet of material13 which is pref-.

erably insulating material such as paper or the hire.

1e indicates the Wire forming the" outer ously, the Wire may beinsulated in any other manner or the turns may be separatedfrom stated;above so'tliat vvirel12'smay 'be bare-wire; and'wh'en such wireis. usedthe 1 turns are properly spaced andiinsulated from or'secondary'coil andthis Wire is here'shownas havlngenamel insulation thereon. ObVleachother in order to be insulatedby the is WOLlIld on the sheet of paper13, such paper preventing the turns thereof from" be understoodthat itis capable of many 7 Changes, therefore, in the construction andarrangement'may be made ,withoutdeparting' from the spirit and scope ,ofthe invent-ionas disclosed-inthe appended,

claims, in which it is my intentionto claimgj all novelty inherent inmyinvention as broadly as pos'siblein view of the prior art.

Letters Patent, is: r

1 A deviceof the character. described com-. I i

prising a cylindrical support having a spiral groove in ltsoutersurface, a ire laid 1n the bottom of said groove, the depth of said theWire laid therein, a sheet of material on said support lying over saidgroove, and

another wirevvound on the outer surface of I sald sheet of material. 1 1

- 2. Adevice of he character described comprising a cylindrical supportof insulating material havinga spiral groove in its outer surface, aWire. laidinthe bottom of said 35 What'I claim as new, and desireto'secure. i

groove being greater than the diameter of groove, the I depth of saidfgroove being greater than the diameter of the Wire laid therein, a sheetof insulating material on e i said support lying over said groove, and.another Wire Wound onthe outer surface of r said sheet ofinsulatingmaterial. :12" indicates the wire' formi n'g the inner or primary.vcoil. Thisgwire is-QWound in the described comprising a cylindricalsupport having a; spiral groove in its outer surface a Wire laid inthebot'tom of said'groovqthe depth of said groove being greater' thanthe diamcter of the Wire laid therein, a sheet of groeiveg and. anotherWill-'6 haviihg 2. diameter small enough :to 'permit-jit ta (internsaidgroove, Wound n-,theqqte1: surface 01- salid sheet of material" andPrvntedfroni; 'entering' said grqove by saidg l shggt; gfi 'p -m V Q "Imateria1 and prevented fromentririg sai A: deVi c f-ofthQham0terudescriba comprislipg a cylindrical; supportfof insulatQ.

, ihgg materlal havingfa; spinal gltorqwe inyits'.

dute uriace u wire laid 'imithepbdttpmsof V said gmdvQ; the; depth" ofsaid? groom;

terial U greater tham'theoffic the wire laid therein, w sheetofinsulatingmaterial on said lying over said grqoveflpnd another wire;having a 'diameter small enough to permit it to ent'fsaid' groove; wound'011' the ogige nisurface bf sid sheet of insulatin' gmowa iby saidisheet fo f' insulating material. testimony whereof- I havehereuntd set

